For the vanilla cream, boil 450 ml milk, cream, sugar, salt and vanilla pulp. Whisk remaining milk, egg yolk and starch. Remove boiling milk from the stove, stir in whisked milk quickly. Heat up again and draw off to a rose. Then put it in a cool place.
Meanwhile, for the sour cream mixture, mix sour cream, eggs, egg yolk, butter, pecorino cheese, starch, lemon peel and salt with the whisks of the hand mixer until smooth. Put the sour cream mixture aside. For the quark oil dough, mix egg, quark, vanilla sugar, sugar, salt, milk and oil. Mix flour and baking powder and knead to a smooth dough with the dough hooks of the hand mixer. Put the dough on the greased fat pan (32x39 cm) of the oven. Mix cooled vanilla cream and sour cream mixture with the whisks of the hand mixer to a smooth dough and spread evenly on the dough. Bake the cake in the preheated oven (electric oven: 175 °C/ gas: level 2) on the lowest shelf for 50-60 minutes. Meanwhile melt the fat for the icing and let it cool down a little. Stir egg yolk and sugar until smooth and stir in the butter, which is not too hot.
Mix cooled vanilla cream and sour cream mixture with the whisks of the hand mixer to a smooth dough and spread evenly on the dough. Bake the cake in the preheated oven (electric oven: 175 °C/ gas: level 2) on the lowest shelf for 50-60 minutes. Meanwhile melt the fat for the icing and let it cool down a little. Stir egg yolk and sugar until smooth and stir in the butter, which is not too hot. Spread the icing evenly on the cake about 12 minutes before the end of the baking time. Take the cake out of the oven, let it cool down and dust with icing sugar